/*
* Head of the kernel - alter with care
*
- * Copyright (C) 2000, 2001 Axis Communications AB
+ * Copyright (C) 2000, 2001, 2010 Axis Communications AB
*
- * Authors: Bjorn Wesen (bjornw@axis.com)
- *
*/
-
+
#define ASSEMBLER_MACROS_ONLY
/* The IO_* macros use the ## token concatenation operator, so
-traditional must not be used when assembling this file. */
#define START_ETHERNET_CLOCK IO_STATE(R_NETWORK_GEN_CONFIG, enable, on) |\
IO_STATE(R_NETWORK_GEN_CONFIG, phy, mii_clk)
-
+
;; exported symbols
-
+
.globl etrax_irv
.globl romfs_start
.globl romfs_length
.globl romfs_in_flash
.globl swapper_pg_dir
-
+
.text
;; This is the entry point of the kernel. We are in supervisor mode.
;; put a nop (2 bytes) here first so we dont accidentally skip the di
;;
;; NOTICE! The registers r8 and r9 are used as parameters carrying
- ;; information from the decompressor (if the kernel was compressed).
+ ;; information from the decompressor (if the kernel was compressed).
;; They should not be used in the code below until read.
-
- nop
+
+ nop
di
;; First setup the kseg_c mapping from where the kernel is linked
#ifdef CONFIG_CRIS_LOW_MAP
; kseg mappings, temporary map of 0xc0->0x40
- move.d IO_FIELD (R_MMU_KBASE_HI, base_c, 4) \
+ move.d IO_FIELD (R_MMU_KBASE_HI, base_c, 4) \
| IO_FIELD (R_MMU_KBASE_HI, base_b, 0xb) \
| IO_FIELD (R_MMU_KBASE_HI, base_9, 9) \
| IO_FIELD (R_MMU_KBASE_HI, base_8, 8), $r0
move.d $r0, [R_MMU_KBASE_HI]
- ; temporary map of 0x40->0x40 and 0x60->0x40
- move.d IO_FIELD (R_MMU_KBASE_LO, base_6, 4) \
+ ; temporary map of 0x40->0x40 and 0x60->0x40
+ move.d IO_FIELD (R_MMU_KBASE_LO, base_6, 4) \
| IO_FIELD (R_MMU_KBASE_LO, base_4, 4), $r0
move.d $r0, [R_MMU_KBASE_LO]
; mmu enable, segs e,c,b,a,6,5,4,0 segment mapped
- move.d IO_STATE (R_MMU_CONFIG, mmu_enable, enable) \
+ move.d IO_STATE (R_MMU_CONFIG, mmu_enable, enable) \
| IO_STATE (R_MMU_CONFIG, inv_excp, enable) \
| IO_STATE (R_MMU_CONFIG, acc_excp, enable) \
| IO_STATE (R_MMU_CONFIG, we_excp, enable) \
move.d $r0, [R_MMU_CONFIG]
#else
; kseg mappings
- move.d IO_FIELD (R_MMU_KBASE_HI, base_e, 8) \
+ move.d IO_FIELD (R_MMU_KBASE_HI, base_e, 8) \
| IO_FIELD (R_MMU_KBASE_HI, base_c, 4) \
| IO_FIELD (R_MMU_KBASE_HI, base_b, 0xb), $r0
move.d $r0, [R_MMU_KBASE_HI]
- ; temporary map of 0x40->0x40 and 0x00->0x00
+ ; temporary map of 0x40->0x40 and 0x00->0x00
move.d IO_FIELD (R_MMU_KBASE_LO, base_4, 4), $r0
move.d $r0, [R_MMU_KBASE_LO]
; mmu enable, segs f,e,c,b,4,0 segment mapped
- move.d IO_STATE (R_MMU_CONFIG, mmu_enable, enable) \
+ move.d IO_STATE (R_MMU_CONFIG, mmu_enable, enable) \
| IO_STATE (R_MMU_CONFIG, inv_excp, enable) \
| IO_STATE (R_MMU_CONFIG, acc_excp, enable) \
| IO_STATE (R_MMU_CONFIG, we_excp, enable) \
;;
;; In both cases, we start in un-cached mode, and need to jump into a
;; cached PC after we're done fiddling around with the segments.
- ;;
+ ;;
;; arch/etrax100/etrax100.ld sets some symbols that define the start
;; and end of each segment.
;; Check if we start from DRAM or FLASH by testing PC
-
+
move.d $pc,$r0
and.d 0x7fffffff,$r0 ; get rid of the non-cache bit
cmp.d 0x10000,$r0 ; arbitrary... just something above this code
;; after init.
.section ".init.text", "ax"
_inflash:
-#ifdef CONFIG_ETRAX_ETHERNET
+#ifdef CONFIG_ETRAX_ETHERNET
;; Start MII clock to make sure it is running when tranceiver is reset
move.d START_ETHERNET_CLOCK, $r0
move.d $r0, [R_NETWORK_GEN_CONFIG]
cmp.d RAM_INIT_MAGIC, $r8 ; Already initialized?
beq _dram_init_finished
nop
-
+
#include "../lib/dram_init.S"
-_dram_init_finished:
+_dram_init_finished:
;; Copy text+data to DRAM
;; This is fragile - the calculation of r4 as the image size depends
;; on that the labels below actually are the first and last positions
;; between the physical start of the flash and the flash-image start,
;; and when run with compression, the kernel is actually unpacked to
;; DRAM and we never get here in the first place :))
-
+
moveq 0, $r0 ; source
move.d text_start, $r1 ; destination
move.d __vmlinux_end, $r2 ; end destination
add.d 0xf0000000, $r4 ; add flash start in virtual memory (cached)
#endif
move.d $r4, [romfs_start]
-1:
+1:
moveq 1, $r0
move.d $r0, [romfs_in_flash]
-
+
jump _start_it ; enter code, cached this time
_inram:
moveq 0, $r0
move.d $r0, [romfs_length] ; default if there is no cramfs
-
+
;; The kernel could have been unpacked to DRAM by the loader, but
;; the cramfs image could still be in the Flash directly after the
;; compressed kernel image. The loader passes the address of the
;; (Notice that if this is not booted from the loader, r9 will be
;; garbage but we do sanity checks on it, the chance that it points
;; to a cramfs magic is small.. )
-
+
cmp.d 0x0ffffff8, $r9
bhs _no_romfs_in_flash ; r9 points outside the flash area
nop
jump _start_it ; enter code, cached this time
_no_romfs_in_flash:
-
+
;; Check if there is a cramfs (magic value).
;; Notice that we check for cramfs magic value - which is
;; the "rom fs" we'll possibly use in 2.4 if not JFFS (which does
bne 2f
nop
- ;; Ok. What is its size ?
-
+ ;; Ok. What is its size ?
+
move.d [$r0 + 4], $r2 ; cramfs_super.size (again, no need to swapwb)
;; We want to copy it to the end of the BSS
add.d $r2, $r0
add.d $r2, $r1
-
+
;; Go ahead. Make my loop.
lsrq 1, $r2 ; size is in bytes, we copy words
bne 1b
nop
-2:
+2:
;; Dont worry that the BSS is tainted. It will be cleared later.
moveq 0, $r0
move.d $r0, [romfs_in_flash]
jump _start_it ; better skip the additional cramfs check below
-
+
_start_it:
;; Check if kernel command line is supplied
move.d ibr_start,$r0 ; this symbol is set by the linker script
move $r0,$ibr
move.d $r0,[etrax_irv] ; set the interrupt base register and pointer
-
+
;; Clear BSS region, from _bss_start to _end
move.d __bss_start, $r0
cmp.d $r1, $r0
blo 1b
nop
-
+
#ifdef CONFIG_BLK_DEV_ETRAXIDE
;; disable ATA before enabling it in genconfig below
moveq 0,$r0
#ifdef CONFIG_JULIETTE
;; configure external DMA channel 0 before enabling it in genconfig
-
+
moveq 0,$r0
move.d $r0,[R_EXT_DMA_0_ADDR]
; cnt enable, word size, output, stop, size 0
move.d $r0,[R_EXT_DMA_0_CMD]
;; reset dma4 and wait for completion
-
+
moveq IO_STATE (R_DMA_CH4_CMD, cmd, reset),$r0
move.b $r0,[R_DMA_CH4_CMD]
1: move.b [R_DMA_CH4_CMD],$r0
nop
;; reset dma5 and wait for completion
-
+
moveq IO_STATE (R_DMA_CH5_CMD, cmd, reset),$r0
move.b $r0,[R_DMA_CH5_CMD]
1: move.b [R_DMA_CH5_CMD],$r0
cmp.b IO_STATE (R_DMA_CH5_CMD, cmd, reset),$r0
beq 1b
nop
-#endif
-
+#endif
+
;; Etrax product HW genconfig setup
moveq 0,$r0
beq 1b
nop
#endif
-
+
moveq IO_STATE (R_DMA_CH8_CMD, cmd, reset),$r0
move.b $r0,[R_DMA_CH8_CMD] ; reset (ser1 dma out)
move.b $r0,[R_DMA_CH9_CMD] ; reset (ser1 dma in)
;; setup port PA and PB default initial directions and data
;; including their shadow registers
-
+
move.b CONFIG_ETRAX_DEF_R_PORT_PA_DIR,$r0
#if defined(CONFIG_BLUETOOTH) && defined(CONFIG_BLUETOOTH_RESET_PA7)
or.b IO_STATE (R_PORT_PA_DIR, dir7, output),$r0
#endif
move.b $r0,[port_pa_data_shadow]
move.b $r0,[R_PORT_PA_DATA]
-
+
move.b CONFIG_ETRAX_DEF_R_PORT_PB_CONFIG,$r0
move.b $r0,[port_pb_config_shadow]
move.b $r0,[R_PORT_PB_CONFIG]
#endif
move.d $r0,[port_g_data_shadow]
move.d $r0,[R_PORT_G_DATA]
-
+
;; setup the serial port 0 at 115200 baud for debug purposes
-
+
moveq IO_STATE (R_SERIAL0_XOFF, tx_stop, enable) \
| IO_STATE (R_SERIAL0_XOFF, auto_xoff, disable) \
| IO_FIELD (R_SERIAL0_XOFF, xoff_char, 0),$r0
- move.d $r0,[R_SERIAL0_XOFF]
+ move.d $r0,[R_SERIAL0_XOFF]
; 115.2kbaud for both transmit and receive
move.b IO_STATE (R_SERIAL0_BAUD, tr_baud, c115k2Hz) \
| IO_STATE (R_SERIAL0_REC_CTRL, rec_par, even) \
| IO_STATE (R_SERIAL0_REC_CTRL, rec_par_en, disable) \
| IO_STATE (R_SERIAL0_REC_CTRL, rec_bitnr, rec_8bit),$r0
- move.b $r0,[R_SERIAL0_REC_CTRL]
-
+ move.b $r0,[R_SERIAL0_REC_CTRL]
+
; Set up and enable the serial0 transmitter.
move.b IO_FIELD (R_SERIAL0_TR_CTRL, txd, 0) \
| IO_STATE (R_SERIAL0_TR_CTRL, tr_enable, enable) \
move.b $r0,[R_SERIAL0_TR_CTRL]
;; setup the serial port 1 at 115200 baud for debug purposes
-
+
moveq IO_STATE (R_SERIAL1_XOFF, tx_stop, enable) \
| IO_STATE (R_SERIAL1_XOFF, auto_xoff, disable) \
| IO_FIELD (R_SERIAL1_XOFF, xoff_char, 0),$r0
- move.d $r0,[R_SERIAL1_XOFF]
+ move.d $r0,[R_SERIAL1_XOFF]
; 115.2kbaud for both transmit and receive
move.b IO_STATE (R_SERIAL1_BAUD, tr_baud, c115k2Hz) \
| IO_STATE (R_SERIAL1_REC_CTRL, rec_par, even) \
| IO_STATE (R_SERIAL1_REC_CTRL, rec_par_en, disable) \
| IO_STATE (R_SERIAL1_REC_CTRL, rec_bitnr, rec_8bit),$r0
- move.b $r0,[R_SERIAL1_REC_CTRL]
-
+ move.b $r0,[R_SERIAL1_REC_CTRL]
+
; Set up and enable the serial1 transmitter.
move.b IO_FIELD (R_SERIAL1_TR_CTRL, txd, 0) \
| IO_STATE (R_SERIAL1_TR_CTRL, tr_enable, enable) \
| IO_STATE (R_SERIAL2_TR_CTRL, tr_bitnr, tr_8bit),$r0
move.b $r0,[R_SERIAL2_TR_CTRL]
#endif
-
-#ifdef CONFIG_ETRAX_SERIAL_PORT3
+
+#ifdef CONFIG_ETRAX_SERIAL_PORT3
;; setup the serial port 3 at 115200 baud for debug purposes
-
+
moveq IO_STATE (R_SERIAL3_XOFF, tx_stop, enable) \
| IO_STATE (R_SERIAL3_XOFF, auto_xoff, disable) \
| IO_FIELD (R_SERIAL3_XOFF, xoff_char, 0),$r0
- move.d $r0,[R_SERIAL3_XOFF]
+ move.d $r0,[R_SERIAL3_XOFF]
; 115.2kbaud for both transmit and receive
move.b IO_STATE (R_SERIAL3_BAUD, tr_baud, c115k2Hz) \
| IO_STATE (R_SERIAL3_REC_CTRL, rec_par, even) \
| IO_STATE (R_SERIAL3_REC_CTRL, rec_par_en, disable) \
| IO_STATE (R_SERIAL3_REC_CTRL, rec_bitnr, rec_8bit),$r0
- move.b $r0,[R_SERIAL3_REC_CTRL]
-
+ move.b $r0,[R_SERIAL3_REC_CTRL]
+
; Set up and enable the serial3 transmitter.
move.b IO_FIELD (R_SERIAL3_TR_CTRL, txd, 0) \
| IO_STATE (R_SERIAL3_TR_CTRL, tr_enable, enable) \
| IO_STATE (R_SERIAL3_TR_CTRL, tr_bitnr, tr_8bit),$r0
move.b $r0,[R_SERIAL3_TR_CTRL]
#endif
-
+
#endif /* CONFIG_SVINTO_SIM */
jump start_kernel ; jump into the C-function start_kernel in init/main.c
-
+
.data
-etrax_irv:
+etrax_irv:
.dword 0
romfs_start:
.dword 0
.dword 0
romfs_in_flash:
.dword 0
-
+
;; put some special pages at the beginning of the kernel aligned
;; to page boundaries - the kernel cannot start until after this
#ifdef CONFIG_CRIS_LOW_MAP
swapper_pg_dir = 0x60002000
-#else
+#else
swapper_pg_dir = 0xc0002000
#endif
projects / cascardo / linux.git / commitdiff